Artificial leg



-A. T. ROWLEY Jan. `12, 1937.

ARTIFICIAL LEG Filed Oct. 29, 1954 INVENTOR 7'?? Patented Jan. 12, 1937 p UNITED STATES PATE T ENCE 10 Claims.

My invention consists in a new and improved knee structure for articial legs to be worn by those who have had an amputation above the knee.

The principal object which I have in view is to provide a better knee action which will improve the walking of the wearer and will give him a better and more natural control in the alternate bending and straightening of the knee in walking and also in sitting down and rising to an erect posture.

Another object is the provision of a noiseless knee action characterized by the complete absence of any clicking noise.

Another object is to prevent lateral or swaying movement in the knee structure or relative lateral movement between the shank and thigh members.

Other objects in view will appear from the following description.

AFor the accomplishment of these purposes, I have invented a leg structure comprising a shank member and a thigh member connected by a pivot bolt, a back-check attached at its lower end to the inside of the back wall of the shank member and provided in its upper portion with a bearing in which the intermediate portion of the pivot bolt is journaled, and an upward and forwardly disposed extension of the back-check which carries a roller under which pass the usual suspension cords, which leg structure in the case of my invention is characterized by the provision of a frame disposed in the rear of the pivot bolt and pivotally connected to the back-check, which frame carries a roller under which said cords also pass, said frame having angular side members, the roller being mounted between the angles of said side members and the depending outer ends of said members, which are preferably rigidly connected together, being attached to the upper end of an elastic artificial muscle whose lower end is connected to the inner rear wall of the shank member. l

The front and rear rollers are preferably so disposed that the runs of the cords passing down around the rollers clear the pivot bolt and the back-check.

Other novel features of construction, and also of arrangement of parts will appear from the following description.

In the accompanying drawing, wherein I have illustrated a practical embodiment of the principles of my invention, Fig. 1 is a vertical section showing the knee portion of an articial leg, the knee control being shown in full side elevation.

Fig. 2 is a top plan view of the knee control and the shank member, the thigh member being omitted for the sake of clearness.'

Fig. El` is a sectional View of the knee control taken along the line 3-3 in Fig. 2, the rollers 5 however being shown in full elevation.

Fig. 4 is av detail in vertical section showing a modication.

Referring to Figs. 1 to 3, inclusive, of the drawing, I represents the upper or thigh member of 10 the artificial leg, and 2 represents the shank member thereof. The two members are formed of wood or other lightweight but suiciently strong material and are hollow, as shown. The lower end of the thigh member extends down 15 into the upper end of the shank member, and the two members are hinged together by the usual tubular pivot bolt 3. At their rear the walls of the two members are cut away as at l and 5, respectively, in the usual manner. 20

6 represents the back-check which is a lever, preferably a metal forging, and whose lower end extends down into the interior of the shank member 2 and is secured as at 'I to the inner back wall of the latter. Adjacent its upper end the backcheck is provided with a cylindrical bearing 8 in which the intermediate portion of the pivot bolt 3 is journaled. By its contact with the wall of the thigh member at 6c as the knee is straightcned, the back-check limits straightening movement.

As shown at 3a the top wall of the bearing 8 may be incomplete.

At its upper end the back-check is provided with an upwardly and forwardly disposed extension which may be formed by a pair of metal plates 9 provided with alined bearing holes I8 through which the pivot bolt extends, and said plates are also secured to the ends of the bearing 8 by the pin II which extends through the wall 40 of the bearing 3 and has its ends riveted over to hold it in place. Thus the plates 9 are rigid relative to the back-check 6.

'I'he outer and upper ends of the plates 9 are connected by the cross pin I2 upon which the 45 roller i3 is journaled between the plates.

The wall of the bearing 8 is intermediately recessed at the rear to receive the pinched together ends of the twin side members I 4 of a frame, and the pin l I extends through said recess 50 and through holes in the ends of said side members whereby the frame is thus pivotally connected to the back-check adjacent the pivot bolt.

The side members I 4 diverge and are then disposed in spaced and parallel relation and curve upwardly and rearwardly, substantially as shown, to avoid all possibility of striking adjacent metal parts as the knee is bent. Said side members are angular, as is clearly illustrated in Figs. 1 and 3, their outer ends depending and being joined together by the bridge member l5 to complete the frame. At their intermediate angles the side members are connected together by the pin i6 upon which isy journaled the roller I'l between said side'members.

I'he bridge member I5 is connected to the upper end of the adjustable resilient muscle vi8 whose lower end is attached to the metal loop I9 which in turn straddles the back-check 6 and has its depending legs secured to the inner surface of the back wall of the shank member 2, as at 20.

2| represents the usual suspension, cords which extend down around the two rollers i3 and il, as illustrated in Figs. l and 3.

When the knee is to be bent in taking a step, the shoulders or body of the wearer are swung slightly forward, as in natural walking, thus increasing the upward tension on the rear roller l1 and the tension on the artificial muscle I8 aids such rst mentioned tension in swinging the shank member 2 rearwardly and upwardly as in natural walking. As the leg is swung forward in completing the step the body of the wearer swings back toward the vertical, thus shifting the upward tension of the suspension cords 2l to the front roller i3 which overcomes the tension of the artificial muscle I8 andswings the shank member 2 toward its straightened position illustrated in Fig. l, when the contact of the back-check with the surface of the thigh member I, as shown in Fig. 1, prevents the shank from swinging forward beyond its straightened position.

In Fig. 4, I show the pvoted frame which carries the rear roller l1 as formed of two side plates Ida having their inner and converged ends pivoted on the pin Il and rigidly connected at their angles by the pin i6 on which the roller Il is mounted. The lower, depending ends of the side plates Ida are rigidly connected by the pin la around which the upper end of the artificial muscle i8 is looped.

It is thus evident that by means of my invention I obtain a knee action which approaches very nearly the knee action of a natural human leg.

One particular advantage is that the swinging frame which carries the rear roller cannot in its movement come into contact with any other 'portion of the leg, either metal or wood, and thus the very unpleasant clicking or knocking noises, which so frequently are noticeable in the use of articial legs, are entirely prevented.

Again by the employment of my invention all lateral movement or swaying is avoided inasmuch as the rear rollers are held against side movement by the frame in which they are mounted and the attachment of the upper end of the artificial muscle to the frame prevents the contraction or stretching of said muscle from causing such lateral swaying as is characteristic of artiicial legs in which the rear roller is mounted on the free upper end of the articial muscle.

I claim:-

1. In an artificial leg comprising a thigh member and a shank member hinged together by a pivot bolt, a back-check secured at its lower end to the rear inside of the shank member and provided with a bearing in which the intermediate portion of the pivot bolt is journaled, an upwardly and forwardly disposed extension of the backcheck, a roller carried by said extension, a frame pivotally attached to the back-check at the rear' of the pivot bolt and below the level of said roller and extending rearwardly from the back check, a second roller mounted in said frame, an artificial muscle connecting the shank member to the pivoted frame and tending to bend the knee, and suspension cords extending down around said rollers.

2. In an articial leg comprising a thigh merrl` ber and a shank member hinged together by a pivot bolt, a back-check secured at itsV lower end to the rear inside of the shank member and provided with a bearing in which the intermediate portion of the pivot bolt is journaled, an upwardly and forwardly disposed extension of the backcheck, a roller` carried by said extension, a frame pivotally attached to the back-check at the rear of the pivot bolt and below the level of said roller and extending rearwardly from the back check, an artiiicial muscle connecting the outer end of said pivoted frame with the shank member and tending to-bend the knee, and a second roller mountedfon said frame intermediate oi its ends, the suspension cords extendingdown around said rollers.

3. In an artificial leg comprising a thigh member and a shank member hinged together by a pivot bolt, a back-check secured at its lower end to the rear inside or" the shank member and provided with a bearing in which the intermediateportion of the pivot bolt is journaled, an up@ wardly and forwardly disposed extension of the back-check, a roller carried by said extension, an angular frame pivotally attached at its front end to the back-check at the rear of the pivot bolt and belowV the level of said roller, the outer end of said frame depending, an artificial muscle connecting the outer end of the frame to the shank member and tending to bend the knee, and a second roller mounted on the intermediate angle of the pivoted frame, the suspension cords extending down around said rollers.

4. In an artiiicial leg comprising a thighmember and a shank member hinged together by a pivot bolt, a back-check secured at its lower end to the rear inside of the shank member and provided with a. bearing in which the intermediate portion of the pivot bolt is journaled, an upwardly and forwardly disposed extension of the backcheck, a roller carried by said extension, an angular frame pivotally attached at its front end to the back-check at the rear of the pivot bolt and below the level of. said roller, an artificial muscle connecting the outer end of the frame to the shank member and tending to bend the knee, and a second roller mounted on the pivoted frame, the suspension cordsv'extending down around said rollers.

5. In an articial leg,` the combination with a thigh member, a shank member and a pivot bolt connecting ther same together, of' a support extending upwardly and forwardly from thepivot bolt and in fixed relation to the shank member, a front roller rotatably mounted on said support, a second support hinged at the rear of the pivot bolt on an axis in fixed relation to the shank member, an artificial muscle connecting the free end of the second support to the rear `of the shank member and tending to bend the knee, a rear roller rotatably mounted on the second support, the suspension cords running down around both the front and the rear rollers, and means 'to limit the upward swing of the second support i front of the pivot bolt should the artificial muscle be released from the second frame, thereby to enable the wearer in such case to bend the knee in walking.

6. In an articial leg, the combination with a thigh member, a shank member, a back-check secured at its lower end to the rear of the shank member and provided with a bearing and a pivot bolt connecting the thigh member and the shank member and having its intermediate portion journaled in the bearing, of a support extending upwardly and forwardly from the back check and in fixed relation thereto, a front roller rotatably mounted on the support, a second support hinged to the back check at the rear of the bearing to swing on a substantially horizontal axis, an artificial muscle connecting the free end of the second support to therear of the shank member and tending to bend the knee, a rear roller rotatably mounted on the second support, the suspension cords running down around both the front and rear rollers, and means to limit the upward swing of the second support whereby to prevent the rear ro-ller moving in front of the pivot bolt should the artificial muscle be released from the second frame, thereby to enable the wearer in such case to bend the knee in walking.

7. In a pivoted knee action control for articial legs, the combination of a control member in fixed relation with the lower leg section in front of the pivoted knee, a second control member pivoted to the lower leg section at a point in back of the pivoted knee, a control cord in operative relation with said control members, and an artiiicial muscle connecting the second control member and the lower leg section to provide a resilient knee bending action in response to the operation of the control cord.

8. In a pivoted knee action control for artificial legs, the combination of a control member in xed relation with the lower leg section in iront of the pivoted knee, a second control membei pivoted to the lower leg section at a point in back of the pivoted knee, a control cord in operative relation with said control members, an artificial muscle connecting the second control member and the lower leg section to provide a resilient knee bending action in response to the operation of the control cord, and means for determining the spaced relation of said control members permitting operation of the knee when the artificial muscle is broken.

9. In an artificial leg having a pivoted knee control, the combination of, a control member in fixed relation with the lower leg section and disposed in front cf the pivotal joint of the knee, a second control member in pivoted relation with the lower leg section at a point in back of the pivotal joint of the knee, a control cord in operative relation with each of said control members, and means resiliently opposing the pivotal movement of the second control member for aiding the control cord in operating the lower leg section.

10. A knee device for use in an artificial leg which comprises a back-check provided with an aperture to receive a knee bolt and having a downwardly extending portion arranged to be secured to a lower leg section, a control member ixed to said back-check and extending upwardly and forwardly of said aperture, and a second control member pivoted to the back-check at a point 1n back of said aperture.

ALBERT T. ROWLEY. 

